Background : Alzheimer`s disease (AD) is characterized by neuronal loss and extracellular senile plaque, whose major constituent is β-amyloid (Aβ), a 39-43 amino acid peptide derived from amyloid precursor protein. In cultures, Aβ directly induce neuronal cell death and can include excessive generation of free radicals and peroxidative injury to proteins, lipids, and other macromolecules. Actinidia arguta, generally called hardy kiwifruit, has been reported to possess anti-inflammatory, anti-allergic and antioxidative properties. The present study aims to investigate the neuroprotective effect of the leaves and stems of A. arguta using in vitro cultured neurons and in vivo experimental animals. Methods and Results : Primary cortical neuronal cultures were prepared using Sprague-Dawley (SD) rat fetuses on embryonic days 15. Neurotoxicity experiments were performed on neurons after 3-4 days in culture. Cultured neurons were treated with 10 μM Aβ (25-35) for 24 h to produce neurotoxicity. In addition, cultured neurons were treated with H2O2 (100 μM) for 15 min and then incubated for 12 h in H2O2-free medium. Viability of cultured neurons was measured by a colorimetric MTT assay. Hoechst 33342 staining of neurons was carried out to examine Aβ (25-35)-induced apoptotic neuronal death. A. arguta over the concentration of 10 to 50 ㎍/㎖ prevented Aβ (25-35) (10 μM)-induced apoptotic neuronal death, and inhibited H2O2-induced decrease of MTT reduction rate. These results suggest that oxidative stress is implicated in Aβ (25-35)-induced neuronal apoptotic death. Memory impairment was produced by intracerebroventricular (i.c.v) microinjection of 15 nmol Aß (25-35) and examined using passive avoidance test in ICR mice. Chronic treatments with A. arguta (14 days, p.o.) protected memory impairment induced by Aß (25-35). Conclusion : The present study suggests that A. arguta has a therapeutic role for preventing the progression of neurodegenerative disease such as AD.

Background : It is well known that Alzheimer`s disease (AD) is associated with neuronal loss and accumulation of extracellular senile plaque, whose major constituent is β-amyloid peptide (Aβ). In cell cultures, Aβ can directly stimulate neuronal cell death and make neurons susceptible to excitotoxicity which may include glutamate release and N-methyl-D-aspartate (NMDA) receptor activation. There are numerous reports in the literature of Cedrela sinensis (CS) for pro-apoptotic effects. It was hypothesized that CS might protect neurons against neurodegeneration in AD due to its pro-apoptotic effects. The current study aimed to determine the protective effect of ethanol extract from the leave of CS on Aβ (25-35)-induced neuronal cell death in primary cultured rat cortical neurons. Methods and Results : Cerebral neurons were collected from embryonic day 15 SD rat fetuses and were cultured on DMEM with serum. Neurotoxicity experiments were proceeded on cultured neurons after 4-5 days in vitro. Cultured neurons were treated with 10 μM Aβ (25-35) for 24 h or 1 mM NMDA for 20 h to induce neuronal death. CS was applied 20 min before the treatment with Aβ (25-35) or NMDA and also present in the medium during the incubations. Colorimetric MTT assay and Hoechst 33342 staining were used to estimate viability of neurons. Western blot analysis was carried out to examine the expression levels of anti-apoptotic and pro-apoptotic proteins. CS (5 and 10 ㎍/㎖) significantly inhibited Aβ (25-35)-induced apoptotic neuronal cell death in cultured cortical neurons. CS also inhibited Aβ (25-35)-induced change of apoptosis-related protein expression in western blot analysis. Furthermore CS (5 and 10 ㎍/㎖) reuduced NMDA-induced neuronal cell death. This study demonstrated that NMDA glutamate receptor activation is related with Aβ (25-35)-induced neuronal apoptotic death. Conclusion : CS protected culterd neurons against Aβ (25-35)-induced neurotoxicity probably via inhibition of NMDA receptor activation. These results suggest that CS can prevent the progression of neurodegenerative disease such as Alzheimer's disease.

Background : Alzheimer`s disease (AD) is characterized by neuronal loss and extracellular senile plaque, whose major constituent is β-amyloid (Aβ), a 39-43 amino acid peptide derived from amyloid precursor protein. In cultures, Aβ can directly induce neuronal cell death and can render neurons vulnerable to excitotoxicity which may involve glutamate release and N-methyl-D-aspartate (NMDA) receptor. Silybum marianum (SM) has been used for centuries to treat liver disease due to its antioxidant, and anti-inflammatory properties. In particular, Silymarin, an active constituent of SM, has been reported to decrease lipid peroxidation. Therefore we hypothesized that SM might protect neurons against neurodegeneration in AD due to its antioxidant and anti-inflammatory activities. In the present study, the protective effect of ethanol extract from the stem of SM on Aβ (25-35)-induced neuronal cell death was examined in primary cultured rat cortical neurons. Methods and Results : Primary cultured cortical neurons were prepared using embryonic day 15 SD rat fetuses. Neurotoxicity experiments were performed on cultured neurons after 4-5 days in vitro. The cells were treated with 10 μM Aβ (25-35) or 1 mM NMDA for 36 h or 14 h, respectively. SM was applied 15 min before treatment of Aβ (25-35) or NMDA and also present in the medium during the incubations. The viability of neurons was monitored using a colorimetric MTT assay and Hoechst 33342 staining. The expression levels of anti-apoptotic and pro-apoptotic proteins were detected by western blot. An Ethanol extract of the stem of SM (10 and 50 μg/ml) significantly prevented Aβ (25-35)-induced apoptotic neuronal cell death in cultured cortical neurons. Furthermore SM inhibited Aβ (25-35)-induced decrease of anti-apoptotic protein, Bcl-2, and increase of pro-apoptotic proteins, Bax and active caspase-2, in western blot analysis. SM (10 and 50 μg/ml) also reduced NMDA-induced neuronal cell death. These results suggest that NMDA glutamate receptor activation is implicated in Aβ (25-35) -induced neuronal apoptotic death. Conclusion : The present study suggests that SM has a possible therapeutic role for preventing the progression of neurodegenerative disease such as Alzheimer's disease.

Background : Ischemic stroke is a common cause of adult disability and death worldwide. Excessive oxidative stress is an important pathogenic mechanism in ischemic stroke. Major reduction of endogenous antioxidative systems increases production of free radicals inducing peroxidation of lipid, protein, and nucleic acid. 1,3-Dipalmitoyl-2-oleoylglycerol (DPOG) is a triglyceride found in oils from various natural sources such as palm kernels, sunflower seeds and rice bran. We found DPOG as an active constituent of rice bran oil. In the present study, we investigated neuroprotective effect of DPOG derived from rice bran oil on excitotoxicity in cultured neurons and on ischemic brain injury in rats. Methods and Results : Transient focal ischemic brain damage was induced by 2 h middle cerebral artery occlusion followed by 24h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, the infarct and edema volume of brain tissue was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining methods. Glutathione concentration and lipid peroxidation rate were measured in brain tissue. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in brain tissue were detected by Western blot. Cerebral cortical neuronal cells were cultured in 15-days-old fetus. Cortical neurons were incubated with 1 mM N-methyl-D-aspartate (NMDA) for 14 h to produce excitotoxicity. Cell viability was measured by MTT assay. DPOG (1-5 mg/kg) significantly reduced MCAO/reperfusion-induced infarction and edema formation, neurological deficits, and brain cell death. Depletion of glutathione level and lipid peroxidation induced by MCAO/reperfusion were inhibited by administration of DPOG. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in ischemic brain were significantly inhibited by treatment with DPOG. DPOG (0.1-10 uM) inhibited 1 mM NMDA-induced neuronal cell death in cultured cortical neurons. Conclusion : From the above results, the present study provides an evidence that DPOG derived from rice bran oil might be effectively applied for the treatment of ischemic stroke.

Background : Alzheimer’s disease (AD) is a neurodegenerative disease characterized by progressive memory loss, cognitive impairment and personality defects accompanied by diffuse structural abnormalities in the brain. The major pathological hallmarks of AD include beta amyloid (Aß) protein deposition, presence of neurofibrillary tangles and neurodegeneration of cholinergic neurons. Aß, a 39-43 amino acid proteolytic fragment of amyloid precursor protein, is the major constituent of the senile plaques. Rice bran, the major byproduct of the rice milling industry, is the source of a high quality vegetable oil. Rice bran oil (RBO) has attracted much medicinal attention for its strong hypocholesterolemic properties because of its balanced fatty acid composition and high levels of antioxidant phytochemicals such as oryzanols, tocopherols and tocotrienols. The present study aims to investigate the protective effect of RBO against Aß (25-35)-induced neurotoxicity in in vitro and in vivo. Methods and Results : Memory impairment was produced by intracerebroventricular (i.c.v) microinjection of 15 nmol Aß (25-35) and measured by passive avoidance test in ICR mice. Glutathione concentration, lipid peroxidation rate and acetylcholine esterase activity were measured in mice brain. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in mice brains were detected by Western blot. Cerebral cortical neuronal cells were cultured from 15-days-old fetus. Cortical neurons were incubated with 10 μM Aß (25-35) for 36 h. Cell viability was measured by MTT assay. Chronic treatments of RBO (0.1-1 ml/kg, 8 days, p.o.) protected against memory impairment induced by Aß (25-35). Depletion of glutathione level, lipid peroxidation and increased acetylcholine esterase activity by the treatment with Aß (25-35) were inhibited by administration of RBO. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in Aß (25-35)-administered mice brain were significantly inhibited by treatment with RBO. RBO (0.1-5ul/ml) inhibited 10μM Aß (25-35)-induced neuronal cell death in cultured cortical neurons. Conclusion : The present study suggests the role of RBO as a promising therapeutic for neurodegenerative diseases like AD and stroke.

Background : Rice bran is the outer brown layer of the rice grain and produced when rice is milled. The basic components of rice bran are fiber, lipids, amino acids, vitamins, and minerals. The oil extracted from this bran is called rice bran oil. Although whole rice bran in itself does not have anti-cholesterol properties, its oil offers significant benefits. Ischemic stroke is a major cause of morbidity and mortality worldwide. The cessation or critical reduction of blood flow in brain during acute stroke results in deprivation of the oxygen and glucose supplies, which can produce a local brain ischemia and injury. It is well established that excitotoxicity, a type of neurotoxicity evoked by elevated extracellular glutamate level, is a primary contributor to ischemic neuronal death. The present study aims to investigate the neuroprotective effect of Rice bran oil (RBO) on ischemic brain injury in rats and on excitotoxicity in cultured neurons. Methods and Results : Transient focal ischemic brain damage was induced by 2 h middle cerebral artery occlusion followed by 24 h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, the infarct and edema volumes of brain tissues were measured using 2,3,5-triphenyltetrazolium chloride (TTC) staining methods. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), inflammatory factors, and anti-apoptotic and pro-apoptotic proteins in brain tissue were detected by Western blot. Primary cortical neuronal cultures were prepared using SD rat fetuses on embryonic days 15. Cortical neurons were treated with N-methyl-D-aspartate (NMDA) (1 mM) for 14 h to produce neuronal cell death. Cell viability was measured by MTT assay. RBO inhibited the formation of infartion and edema in MCAO/reperfusion–induced ischemic brains. The increase of phosphorylated MAPKs, inflammatory factors, and proapoptotic proteins and the decrease of antiapoptotic protein in ischemic brains were significantly inhibited by treatment with RBO. RBO (0.01-1ul/ml) inhibited 1 mM NMDA-induced neuronal cell death in cultured cortical neurons. Conclusion : These results suggest that RBO might be a promising therapeutic for neurodegenerative disease such as stroke.

The present study investigated an ethanol extract (SSB) of a mixture of three medicinal plants of Vitisamurensis, Aralia cordata, and Glycyrrhizae radix for possible neuroprotective effects on neurotoxicity induced byAmyloid β protein (Aβ) (25-35) in cultured rat cortical neurons and antidementia activity in mice. Exposure of cultured cor-tical neurons to 15μM Aβ (25-35) for 36h induced neuronal apoptotic death. At 1-30㎍/㎖, SSB inhibited neuronal death,elevation of intracellular calcium concentration ([Ca²+]i), and generation of reactive oxygen species (ROS) induced by Aβ(25-35) in cultured cortical neurons. Memory impairment and increase of acetylcholinesterase activity induced by intra-cerebroventricular injection of mice with 16nmol Aβ (25-35) was inhibited by chronic treatment with SSB (25, 50 and100㎎/㎏, p.o., for 8 days). From these results, it is suggested that antidementia effect of SSB is due to its neuroprotectiveeffect against Aβ (25-35)-induced neurotoxicity and that SSB may have a therapeutic role in preventing the progression ofAlzheimer’s disease.

The present study investigated an ethanol extract of Chaenomeles sinensis fruit (CSF) for possible neuroprotective effects on neurotoxicity induced by amyloid β protein (Aβ) (25-35) in cultured rat cortical neurons and also for antidementia activity in mice. Exposure of cultured cortical neurons to 10μM Aβ (25-35) for 36 h induced neuronal apoptotic death. At 0.1-10μg/ml, CSF inhibited neuronal death, elevation of intracellular calcium concentration ([Ca2+]i), and generation of reactive oxygen species (ROS) induced by Aβ (25-35) in primary cultures of rat cortical neurons. Memory loss induced by intracerebroventricular injection of mice with 15 nmol Aβ (25-35) was inhibited by chronic treatment with CSF (10, 25 and 50 mg/kg, p.o. for 7 days) as measured by a passive avoidance test. CSF (50 mg/kg) inhibited the increase of cholinesterase activity in Aβ (25-35)-injected mice brain. From these results, we suggest that the antidementia effect of CSF is due to its neuroprotective effect against Aβ (25-35)-induced neurotoxicity and that CSF may have a therapeutic role for preventing the progression of Alzheimer's disease.

Previous work demonstrated that an ethanol extract (HS0608) of a mixture of three medicinal plants of Curcuma longae radix, Phellinus linteus, and Scutellariae radix markedly inhibits Aβ (25-35)-induced neurotoxicity. The present study was performed to further verify the neuroprotective effect of HS0608 on oxidative and ischemic cerebral injury using cultured rat cortical neurons and rats. Exposure of cultured cortical neurons to 100 μM hydrogen peroxide (H2O2) induced neuronal apoptotic death. At 10-100μg/ml, HS0608 inhibited neuronal death, elevation of intracellular calcium concentration ([Ca2+]i), and generation of reactive oxygen species (ROS) induced by H2O2 in primary cultures of rat cortical neurons. In vivo, HS0608 prevented cerebral ischemic injury induced by 2-h middle cerebral artery occlusion (MCAO) and 24-h reperfusion. The ischemic infarct and edema were significantly reduced in rats that received HS0608 (200 mg/kg). These results suggest that the anti-oxidative properties of HS0608 may be responsible for its neuroprotective effect against focal cerebral ischemic injury and that HS0608 may have a therapeutic role in neurodegenerative diseases such as stroke.

The present study investigated an ethanol extract (HS0608) of a mixture of three medicinal plants of Curcumalongae radix, Phellinus linteus, and Scutellariae radix for possible neuroprotective effects on neurotoxicity induced by amyloid βprotein (Aβ) (25-35) in cultured rat cortical neurons and antidementia activity in mice. Exposure of cultured cortical neurons to10µM Aβ (25-35) for 36h induced neuronal apoptotic death. At 1-50㎍/㎖, HS0608 inhibited neuronal death, elevation of intra-cellular calcium concentration ([Ca2+]i), and generation of reactive oxygen species (ROS) induced by Aβ (25-35) in primary cul-tures of rat cortical neurons. Memory loss induced by intracerebroventricular injection of ICR mice with 15 nmol Aβ (25-35) wasinhibited by chronic treatment with HS0608 (25, 50 and 100㎎/㎏, p.o. for 7 days) as measured by a passive avoidance test. Fromthese results, we suggest that the antidementia effect of HS0608 is due to its neuroprotective effect against Aβ (25-35)-inducedneurotoxicity and that HS0608 may have a therapeutic role in preventing the progression of Alzheimer’s disease.

Vitis amurensis (VA; Vitaceae) has long been used in oriental herbal medicine. It has been reported that roots and seeds of VA have anti-inflammatory and antioxidant effects. In the present study, the protective effect of ethanol extract from stems and leaves of VA on hydrogen peroxide (H2O2) (100 μm)-induced neuronal cell damage was examined in primary cultured rat cortical neurons. VA (10-100 μg/ml) concentration-dependently inhibited H2O2-induced apoptotic neuronal cell death measured by 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. VA inhibited H2O2-induced elevation of intracellular Ca2+ concentration ([Ca2+]i) and generation of reactive oxygen species (ROS), which were measured by fluorescent dyes. Pretreatment of VA also prevented glutamate release into medium induced by 100 μm H2O2, which was measured by HPLC. These results suggest that VA showed a neuroprotective effect on H2O2-induced neuronal cell death by interfering with H2O2-induced elevation of [Ca2+]i, glutamate release, and ROS generation. This has a significant meaning of finding a new pharmacological activity of stems and leaves of VA in the CNS.

Moutan cortex, the root bark of Paeonia suffruticosa Andrews (Paeoniaceae), has pharmacological effects such as anti-inflammatory, antiallergic, analgesic and antioxidant activities. We investigated a methanol extract of Moutan cortex for neuroprotective effects on neurotoxicity induced by amyloid β protein (Aβ) (25-35) in cultured rat cortical neurons. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 24 h induced neuronal apoptotic death. Moutan cortex inhibited 10 μM Aβ (25-35)-induced neuronal cell death at 30 and 50 μg/ml, which was measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. Moutan cortex inhibited 10 μM Aβ (25-35)-induced elevation of intracellular calcium concentration ([Ca2+]i), and generation of reactive oxygen species (ROS) which were measured by fluorescent dyes. Moutan cortex also inhibited glutamate release into medium induced by 10 μM Aβ (25-35), which was measured by HPLC. These results suggest that Moutan cortex prevents Aβ (25-35)-induced neuronal cell damage by interfering with the increase of [Ca2+]i, and then inhibiting glutamate release and ROS generation. Moutan cortex may have a therapeutic role in preventing the progression of Alzheimer's disease.

Dried leaves from Cedrela sinensis A. Juss. (CS), have been observed to possess various pharmacological activity and contain various antioxidant constituents. The protective effect of ethanol extract of CS on hydrogen peroxide (H2O2)-induced neurotoxicity was examined using primary cultured rat cortical neurons in the present study. Exposure of cultured neurons to 100 μM H2O2 caused a significant neuronal death as assessed by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. The addition of CS, over a concentration range of 10 to 50μg/ml, concentration-dependently prevented the H2O2-induced neuronal apoptotic death. CS (50μg/ml) significantly inhibited H2O2-induced elevation of the cytosolic Ca2+ concentration ([Ca2+]c), which was measured by a fluorescent dye, Fluo-4 AM. CS (30 and 50μg/ml) inhibited glutamate release and generation of reactive oxygen species (ROS) induced by 100μM H2O2. These results suggest that CS may mitigate the H2O2-induced neurotoxiciy by interfering with the increase of [Ca2+]c, and then inhibiting glutamate release and generation of ROS in cultured neurons.

21 종의 생약 추출물을 선정하여 5 μg/ml의 농도에서 SK-MEL-28 cell 에 대한 세포독성을 조사한 결과 목단피의 메탄올 추출물이 74.3%의 성장율을 보였다. 활성 물질을 찾기 위하여 목단피로부터 silica gel column chromatography를 실시하여 hexane 분획과 EtOAc 분획에서 충 5개의 화합물을 분리하였고 mp, UV, IR, 1H-NMR, 13C-NMR 등 각종 물리, 화학적 data로부터 그 구조를 paeonol (1), benzoylpaeoniflorin (2), benzoic acid (3), 2,5-dihydroxy-4-methoxy-acetophenone (4), paeoniflorin (5)으로 동정하였다. 분리한 물질을 human 피부 암세포인 SK-MEL-28 세포주에 대하여 10 μg/ml의 농도에서 SRB방법으로 세포독성을 측정한 결과 compound 4가 ED50 값이 5.92 μg/ml로 가장 좋은 세포독성을 나타내었다. 이결과는 compound 4가 SK-MEL-28 melanoma 세포주에 대한 새로운 항암 후보 물질임을 제시한다.